[FFmpeg-devel] Make Vorbis encoder not invert samples

[Frank Barchard]

Vorbis encoder is inverting samples, which makes no sense.
Removing it makes it easier to look at the samples and try to figure out why
quality is low.

Index: libavcodec/vorbis_enc.c
===================================================================
--- libavcodec/vorbis_enc.c     (revision 23202)
+++ libavcodec/vorbis_enc.c     (working copy)
@@ -915,7 +915,7 @@
             float * offset = venc->samples + channel*window_len*2 +
window_len;
             j = channel;
             for (i = 0; i < samples; i++, j += venc->channels)
-                offset[i] = -audio[j] / 32768. / n * win[window_len - i -
1]; //FIXME find out why the sign has to be fliped
+                offset[i] = audio[j] / 32768. / n * win[window_len - i -
1];
         }
     } else {
         for (channel = 0; channel < venc->channels; channel++)
@@ -932,7 +932,7 @@
             float *offset = venc->saved + channel * window_len;
             j = channel;
             for (i = 0; i < samples; i++, j += venc->channels)
-                offset[i] = -audio[j] / 32768. / n * win[i]; //FIXME find
out why the sign has to be fliped
+                offset[i] = audio[j] / 32768. / n * win[i];
         }
         venc->have_saved = 1;
     } else {